Bobbin thread replenishing means in sewing machine loop taker



Dec. 31, 1963 5. J. KETTERER 3,115,855

BOBBIN THREAD REPLENISHING MEANS IN SEWING MACHINE LOOP TAKER Filed Aug.25, 1961 5 Sheets-Sheet 1 INVENTOR. STANLEY J. KETTERER BY ATTORNEYWITNESS M i Q Dec. 31, 1963 5.1 KETTERER 3,115,355

BOBBIN THREAD REPLENISHING MEANS IN SEWING MACHINE LOOP TAKER Filed Aug.25, 1961 1 3 Sheets-Sheet 2 \V I0] 44 v F lg. 9.

x INVENTOR. 1a? a '05 STANLEY J. KETTERER BY WITNESS I04 1,.

ATTORNEY Dec. 31, 1963 5. J. KETTERER. 3,115,855

BOBBIN THREAD REPLENISHING MEANS IN SEWING momma LOOP TAKER Filed Aug.25. 1961 3 Sheets-Sheet 3 INVENTOR. STANLEY J. KETTERER WITNESS me Bywayg a ATTORNEY United States Patent 3,115,855 BGBBIN THREADREPLENlSI-HNG MEANS IN SEWING MACHINE LOOP TAKER Stanley J. Ketterer,Morris Plains, N.J., assignor to The Singer (Company, a corporation ofNew Jersey Filed Aug. 25, 1961, Ser. No. 133,896 8 Claims. (Cl. l12184)This invention relates to sewing machines for producing lock stitches,Federal type stitch #301, and more particularly, to a novel and improvedmechanism in a lock stitch sewing machine for replenishing under orlocking thread on a bobbin in place in the loop taker during acontinuation of the same interrelated motion of the needle and looptaker as is required for the formation of lock stitches.

The United States patent application of S. I. Ketterer and W. Herron,Serial No. 736,748, filed May 21, 1958, now Patent No. 3,012,530,discloses a mechanism for replenishing locking thread on the bobbin inplace in a loop taker of a lock stitch sewing machine in which thethread to be replenished is introduced to the bobbin by a means forgripping the needle thread on the loop taker beak. The loop taker thenbecomes a winding member at least to initiate the winding of the bobbin.While this prior mechanism will operate with any type of lock stitchsewing machine, it has gained acceptance primarily in cyclicallyoperated machines, such as button sewers, tackers, etc. because when itis used the thread replenishing process is best begun with a relativelyshort tag end of needle thread extending from the needle eye, and themeans for gripping the thread on the loop taker must be operated at justthe proper time in the thread replenishing operation. In cyclicallyoperated machines, the stop motion device automatically positions theparts in such a position between cycles that at the beginning of eachcycle no appreciable thread is drawn backward through the needle eye andas a result these machines can be and regularly are started with arelatively short end of needle thread extending from the needle eye.Moreover, since cyclic machines must always start in the same positionof parts, precise timing of the thread gripping means presents noparticular problems.

With non-cyclic sewing machines, such as family sewing machines,however, there is no stop motion device. With family sewing machines,while it is possible for the operator always to stop the machine in thesame position of parts, and particularly in a stopped position in whichno appreciable thread will be drawn backwardly through the needle eyeupon the succeeding initiation of sewing, many operators are notfastidious about such manipulation. It is a general practice in familymachine operation to obviate any danger of unthreading the needle bydrawing out several inches of needle thread and placing it under thepresser foot prior to initiation of sewing. Thus, to apply thereplenishing mechanism of the above referenced United States patentapplication Serial No. 736,748 to a family sewing machine requires ofthe operator a manipulation which is opposite to that with which mostoperators are accustomed and opposite to that which is ingrained and hasbecome second nature to most proficient family type sewing machineoperators.

The United States patent application of R. E. Johnson, Serial No.96,579, filed March 17, 1961, discloses a mechanism for replenishinglocking thread on a bobbin in place in the loop taker in which theconventional thread manipulation by the loop taker during eachreciprocation of the needle is utilized to form and cast successiveloops of thread on the bobbin during the replenishing process. With suchmechanism, while the operator may manipulate the needle thread end inthe conventional or accustomed manner, the replenishing operation can beslower 3,115,855 Patented Dec. 31, 1963 "ice than that which would beobtained with the mechanism of the aforementioned United Statesapplication Serial No. 736,748 since, with the mechanism of UnitedStates patent application No. 96,579, only one loop is cast on thebobbin during each stitch forming motion, whereas certain loop takers,such as rotary hooks, partake of a plurality of revolutions for eachstitch forming motion.

It is an object of this invention to provide a novel thread replenishingmechanism for a lock stitch sewing mechanism in which the advantages ofeach of the prior known mechanisms are attained.

It is an object of this invention to provide a thread replenishingmechanism operable with a long starting end of needle thread which as iscustomary in family sewing machine operation, may be placed beneath thepresser foot prior to initiation of sewing.

It is another object to provide a thread replenishing mechanism in whichinitial introduction of the needle thread to the bobbin in place in theloop taker is accomplished without a gripping means for clamping thethread on the loop taker beak. Still another object of this invention isto provide a thread replenishing mechanism of the above character inwhich the thread may be wound on the bobbin in place in the loop takerat the rate of a plurality of revolutions for each reciprocation of theneedle.

It is an object of this invention to provide a novel means for causingthe thread loop from the needle to be secured to the bobbin within theloop taker so as to be wound thereon when the bobbin is driven, and toprovide a means for severing one of the limbs of a thread loop sosecured to the bobbin only after the thread loop has been secured to thebobbin.

With the above and additional objects and advantages in view as willhereinafter appear, this invention comprises the devices, combinations,and arrangements of parts hereinafter described and illustrated in theaccompanying drawings of a preferred embodiment in which:

FIG. 1 represents a front elevational view of a sewing machine havingthe thread replenishing mechanism of this invention applied thereto,

FIG. 2 represents an enlarged top plan View of the loop taker of thesewing machine of FIG. 1, including a fragment of the work support withportions broken away to illustrate the loop taker,

FIG. 3 is a cross-sectional view of the loop taker including fragmentsof the presser device, needle, feed dog and work support takensubstantially along line 3-3 of FIG. 2,

FIGS. 4, 5, 6 and 7 represent top plan views of the loop taker of thisinvention in various positions during the replenishment of thread on abobbin in place in the loop taker; that is, in FIG. 4 during seizure andexpansion of a loop of thread by the loop taker, in FIG. 5 aftercast-off of the expanded loop of thread from the loop taker, in FIG. 6after manipulation of the loop of thread into a relation secured forrotation with the bobbin and during the severance of one of the limbs ofthe loop, and in FIG. 7 after continued winding of thread on the bobbin.

FIG. 8 is a cross-sectional view of the loop taker taken substantiallyalong line 88 of FIG. 7 and including fragments of the work support feeddog presser foot, and the sewing threads during a typical sewingoperation, and

FIG. 9 is a cross-sectional view of a portion of the loop taker takensubstantially along line 99 of FIG. 5.

Referring particularly to FIG. 1 of the drawings, the sewing machine inwhich this invention is illustrated comprises a frame including a bed11, a standard 12 rising from the bed, and a bracket arm 13 extendingfrom the standard over the bed. The bracket arm supports a presser bar14 spring biased downwardly and to which a presser foot is secured so asto bear against a throat plate 16 carried on the bed. Also carried inthe bracket arm is an endwise reciprocable needle bar 17 to which isclamped an eye-pointed thread carrying needle 18. The

needle is reciprocated by a driving connection (not shown) with a rotarymain shaft 19 journaled lengthwise inthe bracket arm. The main shaftcarries at the free extremity a balance Wheel 20 and may be actuated bya conventional operator influenced electric motor (not shown) by way ofa drive gear 21 on the mam shaft. Also carried in the bracket arm anddriven by the maln shaft is a needle thread take-up lever'22.

The needle thread is stored'on a spool 23 supported on a spool pin 24 onthe bracket arm and is adapted to be unwound axially from the spoolabout a thread guard 25 on the spool pin. The thread is directed fromthe spool through the thread guides 26 and 27 along the top of thebracket arm, through a light pretension device 28 to prevent spillingfrom the spool, and to a conventional thread tensioning device 29carried on the bracket arm. From the tensioning device, the thread isdirected to a check spring 30, a thread guide 31, and through the takeuplever '22. From the take-up lever to the eye of the needle, the threadis directed through a thread guide 32 and a light tensioning device 33on the bracket arm, and a thread guide 34 on the needle bar.

Journaled in the bed beneath the throat plate is a loop taker indicatedgenerally as which is carried by a loop taker shaft 41. The loop takeris driven from the main shaft by three meshing pairs of spiral bevelgears 4242, 4343 and 44- -44 and by Way of a bed shaft 45 and a shaft 46journaled vertically within the standard. The loop taker disclosed inthe accompanying drawings is a vertical axis'rotary hook and ispreferably driven at a speed of two revolutions for each reciprocationof the needle.

The main shaft, bed shaft, vertical standard shaft, and

the gear connections therebetween provide a drive means 1y through slots48 in the throat plate in opposition to the presser foot to transportwork fabrics across the bed during stitching. Preferably the workfeeding mechanism includes a throw out device (not shown) for renderingthe feed mechanism ineflective.

Indicated at 50 is a control dial by which the operator of the machinemay position the various parts and devices of the sewing machine inreadiness for replenishment of a supply of lockingthread in the looptaker.

While the control dial and the linkages actuated thereby do not form adirect part of this invention these linkages are shown in 'theaccompanying drawings. References ma be had'to copending United Statespatent application of'Stanley I. Ketterer, Serial No. 133,911, filedAugust 25, 1961, for a detailed disclosure of this control mechanism aswell as for a detailed disclosure of the throw out device for the workfeeding mechanism thereof.

It will be suificient for an understanding of this invention toappreciate that the operator by turning the control dial 50 apredetermined increment, may release the thread tensioning device '29,effect'throw out of the work feeding mechanism, shift a locking threadreplenishing lever 51 fulcrumed at 52 beneath the bed, into effectiveposition, and also regulate the amount of locking thread replenished byengaging the drive means 19, 45, 46 for the stitch forminginstrumentalities gradually to return the control dial to the initialposition in which the various parts will be restored to positionsrequired for sewing. The locking thread replenishing lever 51 is pivotedto a link 53 extending upwardly through the standard 12. A

1 projection 54 on the link 53 is engaged by a projecting arm 55 of alever 56 which is fulcrumed in the standard. The lever 56 may bedepressed by a cam collar 57 secured for turning movement with thecontrol dial 50.

Referring particularly to FIGS. 2 and 3, the loop taker and associatedparts of this invention will now be described. The loop taker is formedwith a cup-shaped body portion 68 which is provided internally with anannular bearing rib 61. A loop seizing beak 62 is formed on thecup-shaped body portion and pointed inwardly so as to pass adjacent tothe needle 18 to seize a loop of needle thread therefrom as the needlepenetrates a needle aperture 63 in the throat plate.

Journaled within the cup-shaped loop taker body portion is an annularbobbin case 64 formed about less than half of its periphery with aportion having therein a bearing raceway 65 complemental to the looptaker bearing rib. Joining the bearing raceway portion of the bobbincase is a substantially circular arm' 66 completing the annular bobbincase. The bobbin case is formed with spaced abutments 67 and 68 whichcooperate with spaced fingers'69 and 70 of a bracket member 71 slidablysupported on the bed 11 to constrain the bobbin case bearing raceway injournaled relation on the loop taker bearing riband also to restrain thebobbin case from rotation. The bracket member 71 may be flexed slightlyto disengage a notch 72 thereon from the head of a screw 73 secured inthe bed so that the bracket member may be shifted away from the looptaker to permit removal of the bobbin case from the loop taker. A leafspring 74 carried on the bracket member and extending between the finger7t) and the bobbin case abutment 68 serves to cushion any vibration ofthe bobbin case.

The exposed face of the bobbin case is formed with an annular seat 75which loosely accommodates the periphery of one flange 76 of a bobbin.Passing through a clearance aperture in the bobbin flange 76 is a screw77 having a crowned head 78 surmounted by a cylindrical pin 79. Threadedon the screw 77 and thus securedto the flange 76 is the hub portion 88of the bobbin preferably formed integral with a bobbin flange 81. Thebobbin hub portion 80 is preferably frustoconical tapering 7 toward thebobbin flange 76 and the outer edge of the a wedge shaped threadgripping groove 82. The remaining of the periphery of the outer edge ofthe hub is undercut forming with the bobbin flange 76 a clearance groove83 within which a thread may slide readily. The underside of the bobbinflange 81, i.e., that opposite to the hub portion 80 is formed with aC-shaped circular slot 84 by which, as will be described hereinbelow,the bobbin may be driven with and in a predetermined angular relation tothe loop taker.

A bobbin hold-down arm 96 is pivoted on the bobbin case on a pivot pin91 and extends radially across the bobbin. A bearing aperture 92 formedin the hold-down arm embraces the cylindrical pin 79 on the bobbin tocenter the bobbin in the bobbin case. A leaf spring 93 carried beneaththe bobbin case and influenced by the adjusting screw 94 bears upwardlyagainst the bobbin hold down arm fut the opposite side of the pivot pin91 from the bearing aperture 92 so as to urge the bobbin flange 76 intofrictional engagement with the annular seat 75 in the bobbin case thusto provide a tension resisting withdrawal of thread wrapped on thebobbin.

Disposed within the loop taker body portion 60 and between the looptaker and the bobbin is an annular bobbin winding member 198 formed withan upstanding annular rib 101 proportioned slightly larger in diameterthan the bobbin flange 81 so as to accommodate axial movement of thebobbin winding member into an enveloping relation with lthe bobbinflange 81. The bobbin winding member is made fast on a rod 102 which isaxially slidable Within a bore 103 formed in the loop taker shaft 41.Beneath the loop taker shaft, the rod carries fast thereon an anglebracket 104 projecting into interlocking relation within a notch 105 outinto the bevel gear 44 fast on the loop taker shaft. The bottomextremity of the rod 102- is threaded to accommodate a clamp nut 106 bywhich a leaf spring 107 is secured thereon. The leaf spring 107 is fixedin turn to the thread replenishing lever 51 so that in the effectiveposition of the lever 51 the bobbin winding member 100 will be elevatedinto engagement with the bobbin with the rib 10 1 thereon enveloping thebobbin flange 81. A pin 10 8 upstanding from the bobbin winding membercooperates with the C-shape-d slot 84 in the bobbin to provide anaxially separable driving connection between the bobbin winding memberand the bobbin. Referring to FIGS. 3, 4, and 6, the relative angularposition of the C-shaped slot in the bobbin, the pin 108, the anglebracket 104 and the notch 105 in the gear 44 is such that 'when theseparable driving connection 108, 84 is engaged the thread grippinggroove 82 between the bobbin hub 80 and the bobbin flange 76 will extendangularly about the 180 which is immediately in advance of the loopseizing beak 62 of the loop taker.

The annular rib 101 on the bobbin winding member is formed with anauxiliary thread engaging hook 110 formed in the throat of which is asharpened thread cutting edge 111 which may of course be provided by adetaohable knife blade. The hook 110 and knife 1-11 are preferably timedon the bobbin winding member to trail the loop seizing beak of the looptaker so as to engage a thread loop only after it has been cast off theloop seizing beak of the loop taker as will be described hereinbel ow.

In order to encourage seizure by the hook 110 of a thread cast off theloop taker loop seizing beak, the bobbin case arm 66, from a pointapproximately 180 opposite the path of the needle to a pointapproximately 270 from the path of the needle considered in thedirection of rotation of the loop taker as indicated by the arrow inFIG. 2, is formed with a depending cam portion 115. As illustrated inFIG. 9, this cam portion, which is disposed along that path of travel ofthe loop taker beak at which cast off of the thread loop therefromoccurs, serves to deflect the cast off loop sharply over the annular rib101 so as to encourage seizure of the cast off thread loop by the hook110 and the knife 111.

In order to prevent seizure by the hook 110 and severance by the knife11-1 of that limb of thread which extends from the needle to the bobbin,a recess 116 is formed beneath the bobbin case arm 66 opposite theneedle aperture 63 which recess, as illustrated in FIG. 8, provides fora lead of the thread from the bobbin to the needle sufficiently abovethe level of the annular rib 101 as to preclude seizure thereof by thehook 110.

Should the bobbin be -wound by hand outside the loop taker, or removedand replaced after having been wound in place in the loop taker, sewingcan be accomplished with a thread lead from the bobbin over the arm 66of the bobbin case as illustrated in dashed lines in FIG. 8. Such athread lead is far easier for an operator to accomplish and tofacilitate such passage of the thread the top of the bobbin case arm 66is preferably relieved as at 117 I to provide clearance for such threadlead.

Operation In the formation of a lock stitch with the mechanism of thisinvention, the loop taker loop seizing beak 62 upon seizing a loop ofthread from the needle carries the seized loop against the bearingraceway 65 of the bobbin case which divides the loop into two limbs ofwhich one is carried beneath the bobbin and the other is carried overthe bobbin by continued rotation of the loop taker. After the loop takerhas completed approximately one half revoltuion beyond loop seizure, theaction of the needle thread take-up lever draws or casts off the loopfrom the loop seizing beak and draws the needle thread loop about thebobbin and from the loop taker, thus concatinating the needle threadwith the bobbin thread if a bobbin thread is present.

In order to replenish thread on the bobbin, the tag end of threadextending from the eye of the needle must first be anchored relativelyto the sewing machine frame, and this may be accomplished in a varietyof ways. If replenishment is required during a stitching operation whenthe needle thread extends to stitches in a work fabric, anchoring of thethread end is accomplished by simply maintaining the work in placebeneath the presser foot. The thread end may be anchored by simplyplacing it between the presser foot 15 and the throat plate 16 asillustrated in FIG. 3, or the thread end may be grasped by the operator,or secured in any known thread nipping device (not shown). The threadend from the needle eye being anchored, the machine operator replenishesthread on the bobbin by simply turning the control dial sufficiently tocarry the thread replenishing lever 51 into effective position andthereafter operating the sewing machine.

Shifting of the thread replenishing lever 51 into effective positionwill lift the bobbin winding member 100 into engagement with the bobbinas illustrated in FIG. 3. In this position of parts, as the loop takerloop seizing beak 62 seizes and expands a loop of needle thread, thatlimb of the seized loop which is ordinarily carried beneath the bobbinis deflected by the annular rib 101 of the bobbin winding member betweenthe bobbin flanges 76 and S1 and onto the hub portion 80 of the bobbinas illustrated in FIGS. 4 and 5.

After the loop taker loop seizing beak 62 has traveled approximately 180beyond loop seizure as illustrated in FIG. 5, the thread loop will becast off the loop seizing beak 62 by the action of the take-up lever 22.The thread introduced to the bobbin hub portion 80 will at this stage ofthe operation be disposed in the clearance groove 83 on the bobbin huband will therefore be free of the bobbin hub so that the action of thetake-up lever will be effective to draw or cast the thread loop from thebeak 62.

Referring to FIGS. 5 and 9, the thread loop when cast I off the looptaker loop seizing beak will be held by the depending cam portion 115 ofthe bobbin case arm .66 directly in the path of the auxiliary threadengaging hook and knife edge 111 on the annular rib 101 of the bobbinwinding member. When the loop is cast off the beak 62 and no longercarried thereby about the bobbin case, the auxiliary hook 110 trailingthe loop taker beak moves into engagement with the loop of thread andcarries the seized loop into the position illustrated in FIG. 6.

In the position of FIG. 6, the thread gripping groove 82 associated withthe bobbin hub will have been turned into engagement with the thread onthe hub and the thread leading to the needle eye will have thus beensecured to the bobbin. The knife edge 111 then operates on a length ofthread which is anchored relatively to the machine frame at one end andis anchored on the bobbin at the other end so that the thread can besevered cleanly.

After severance of the tag end of thread by the knife edge 111, windingof thread on the bobbin will continue by virtue of the drivingconnection 84108 between the bobbin and the bobbin winding member, asillustrated in FIG. 7.

The thread winding process proceeds during continued continuation of thesame interrelated motion of the needle and loop taker as is required forthe formation of lock stitches. Lock stitches are not made during thewinding process and moreover, the loop taker loop seizing beak cannotseize a second loop of thread from the needle after bobbin winding hascommenced because the tag end of thread from the needle eye then extendsto the bobbin and there is no possibility of formation of a loop ofthread for seizure by the beak 62.

Winding thus continues until the control disk 50 has been returned tothe sewing position at which time the bobbin replenishing lever 51 isshifted out of effective bobbin Winding position and the bobbin windingmember 100 is retracted to the position illustrated in FIG. 8. Theneedle thread tension device 29 and the'work feeding mechanism aresimultaneously rendered effective so that upon further interrelatedmotion of the needle and loop taker, lock stitches will be formed in theconventional manner.

Having thus described the nature of this invention, what I claim hereinis:

1. In a lock stitch sewing machine having a frame a thread carryingneedle, a loop taker, a loop seizing beak formed on said loop takeradapted to seize, manipulate and shed loops of needle thread, a threadcarrying bobbin, means for constraining said bobbin in place in saidloop taker, and drive means permanently interconnecting said needle andloop taker for interrelated motion required for the formation of lockstitches, means for replenishing thread on said bobbin in place in saidloop taker during interrelated motion of said needle and loop taker asrequired for the formation of lock stitches comprising, means foranchoring a free end of thread carried by said needle relatively to saidsewing machine frame, threadguide means associated with said loop takerfor directing into said bobbin a loop of said anchored needle threadseized and manipulated by said loop taker loop seizing beak, threadgripping means on said bobbin for securing thereon that loop of threaddirected intosaid bobbin by said thread guide means, thread severingmeans carried for movement with said loop taker in a path effective tosever that limb of a loop of needle thread extending from said threadgripping means on said bobbin to said thread anchoring means, and drivemeans for rotating said bobbin during continued interrelated motion ofsaid needle and loop taker as is required for the formation of lockstitches.

'2. In a lock stitch sewing machine having a thread carrying needle, aloop taker, a loop seizing beak formed on said loop taker adapted toseize and manipulate loopsof needle thread, a needle thread take-upmember adapted to cast off said loop seizing beak loops of threadmanipulated thereby, a thread carrying bobbin freely journaled in placein said loop taker, constraining means for maintaining said bobbinfreely journaled in said loop taker, and drive means permanentlyinterconnecting said needle,

loop taker and take-up member for interrelated motion required for theformation of lock stitches, means for replenishing thread on saidbobbinin place in said loop taker during interrelated motion of said needle,loop taker and take-up member as required for the formation of lockstitches comprising, thread guide means associated with said loop takerand effective during at least one seizure and manipulation of a needlethread loop by said loop taker loop seizing beak for directing a loop ofneedle thread into said bobbin, means for providing free movement ofsaid loop of needle thread along its own length relatively to saidbobbin during cast-off of said needle thread loop from said loop takerloop seizing beak by said take-up member, thread gripping means on saidbobbin effective to secure that loop of thread directed into said bobbinby said thread guide means after castofr of said needle thread loop fromsaid loop takerseizing beak by said take-up member, and drive means forrotating said bobbin during continued interrelated motion of saidneedle, loop taker, and thread take-up member as is required for theformation of lock stitches.

3. In a lock stitch sewing machine having a thread carrying needle, aloop taker, a loop seizing beak formed on said .loop taker adapted toseize, manipulate and shed;

loops of needle thread, a thread carrying bobbin, means for constrainingsaid bobbin in place in said loop taker, and drive means permanentlyinterconnecting said needle and loop taker for interrelated motionrequired for the formation of lock stitches, means for replenishingthread I '8 on said bobbin inplace in said loop-taker duringinterrelated motion of said needle and loop taker as required for theformation of lock stitches comprising, a bobbin winding member disposedbetween. said loop taker and said bobbin, means for rotating said bobbin.winding member in timed relation with the motion of said loop takerrequired for the formation of lock stitches, means forshifting saidbobbin winding member relatively to said bobbin into an overlappingrelation thereto for directing a loop of needle thread seized andmanipulated by said loop taker beak into said bobbin, a thread engaginghook formed on said bobbin winding member and disposed trailing saidlooptaker loop seizing beak so as to engage and continue. to wrap on saidbobbin said loop of needle thread manipulated by said loop taker loopseizing beak only after said thread loop has been shed from said loopseizing beak, thread severing means associated with said bobbin windingmember for severing the thread engaged by said thread engaging hookafter said thread has been wrapped on said bobbin by said threadengaging hook sufficiently to snub said thread on said bobbin, andseparable drive means between said bobbin winding member and said bobbinfor driving said bobbin when said bobbin winding member is shifted intooverlapping relation there- 4. In a lock stitch sewing machine having, athread carrying needle, a loop taker, a loop seizing beak formed on saidloop taker adapted to seize, manipulate and shed loops of needlethread,a thread carrying bobbin including a pair of circular concentric flangesspacedaxially by a hub, means for constraining said bobbin in place insaid loop taker, and drive means permanently interconnecting said needleand loop taker for interrelated motion required for the formation oflock stitches, means for replenishing thread on said bobbin in place insaid loop taker during interrelated motion of said needle and loop takeras required for-the formation of lock stitches-comprising, a

said annular peripheral flangeoverlaps one of said bobbin flanges fordirecting a loop ofneedle thread seized and manipulated by said looptaker beak between said bobbin flanges and onto said bobbin hub, athread engaging hook formed on the peripheral'flange of said bobbinwinding member and disposed trailing said loop taker loop seizing beakso as to engage and continue to wrap on a said bobbin hub said loop ofneedle-thread manipulated by said loop taker loop seizing beak onlyafter said thread loop has been shed from said loop seizing beak, threadcutting knife means associated with said bobbin winding member forsevering the thread engaged by said'thread engaging hook after saidthread has been: wrapped on said bobbin hub by said thread engaging,hook sufficiently to snub said thread .on said bobbin, and separabledrive means between said bobbin windingmember and said bobbin fordriving said bobbin when the peripheral flange vof said bobbin windingmember is shifted into overlapping relation thereto.

5. In a lock stitch sewing-machine having a thread carrying needle, aloop taker, a loop seizing beak formed on said loop taker adaptedtoseize, manipulate and shed loops of needle thread, a thread carryingbobbin,

,means for constraining said bobbin inplace in said loop taker, anddrive means permanentlyinterconnecting said needle tandrloop taker forinterrelated motion required for the formation of lock stitches, meansfor replenishing thread on said bobbin in place in said loop takerduring interrelated motion of said needle and loop taker as required forthe formation of lockstitches comprising a bobbin winding memberdisposed between said loop taker and said bobbin, means for rotatingsaid bobbin winding member in timed relation with the motion of saidloop taker required for the formation of lock stitches, means forshifting said bobbin winding member relatively to said bobbin intooverlapping relation thereto, a thread cutting knife means formed onsaid bobbin winding member and disposed trailing said loop taker loopseizing beak, a separable driving connection between said bobbin windingmember and said bobbin for driving said bobbin when said bobbin windingmember is shifted into overlapping relation thereto, means for anchoringa free end of thread carried by said needle relatively to said sewingmachine, means for operating said drive means while said threadanchoring and said shifting means are effective so as to influence inseriatim seizure, manipulation into said bobbin, shedding of a loop ofthread from said needle by said loop seizing beak, severance of thatlimb of said shed eedle thread loop leading to said anchoring means bysaid thread cutting knife means, and rotation of said bobbin to windthereon thread from said needle, and means for shifting said bobbinwinding member out of overlapping relation with said bobbin so as tocause the formation of lock stitches upon further interrelated motion ofsaid needle and loop taker.

6. In a lock stitch sewing machine having a thread carrying needle, arotary loop taker formed with a loop seizing beak, a needle threadtake-up mechanism and a drive means permanently interconnecting saidneedle, loop taker, and take-up mechanism for interrelated motion as isrequired for the formation of lock stitches, a thread carrying bobbinincluding a pair of axially spaced flanges and a hub extending betweensaid flanges, means for constraining said bobbin axially in said looptaker, means for replenishing on said bobbin in place in said loop takerthread from said thread carrying needle during continued interrelatedmotion of said needle, loop taker and take-up mechanism as is requiredfor the formation of lock stitches comprising a thread gripping meansformed about substantially 180 of said bobbin hub, a thread windingmember disposed between said loop taker and said bobbin, meansconstraining said thread winding member for rotation with the loop takerand for movement axially of said loop taker and relatively to saidbobbin, thread guiding means carried by said bobbin winding member andeffective when said bobbin winding member is shifted axially toward saidbobbin to guide a needle thread loop seized by said loop seizing beakbetween said bobbin flanges and onto said bobbin hub, an axiallyseparable driving connection between said bobbin winding member and saidbobbin and effective when said bobbin winding member is shifted axiallytoward said bobbin to constrain said bobbin for rotation with said looptaker with said thread gripping means on said bobbin hub extending oversubstantially that 180 immediately in advance of the loop taker loopseizing beak, and a thread severing knife carried by said bobbin windingmember and disposed trailing said loop taker loop seizing beak.

7. in a lock stitch sewing machine having a frame, an endwisereciprocatory thread carrying needle carried on said frame, said framebeing formed with a needle aperture for penetration by said needle, arotary loop taker having a loop seizing beak carried at the oppositeside of said needle aperture from said needle, a heedle thread take-upmechanism, and drive means permanently interconnecting said needle looptaker and take-up mechanism for operation in timed relation required forthe formation of lock stitches including movement of said loop seizingbeak past said needle aperture during needle penetration for thread loopseizure by said beak and operation of said take-up mechanism to castsaid seized thread loop from said beak after approximately of loop takerrotation beyond thread loop seizure, a bobbin case journaled in saidloop taker, interengaging rotation restraining means on said frame andsaid bobbin case, a thread carrying bobbin freely journaled in saidbobbin case, means for replenishing thread from said thread carryingneedle onto said bobbin in place in said bobbin case during continuedmovement of said needle loop taker and take-up mechanism in time;relation required for the formation of lockstitches, said meanscomprising, means for anchoring a tag end of thread carried by saidneedle relatively to said sewing machine frame, thread guiding means forintroducing a loop of needle thread seized by said loop seizing beakinto said bobbin, means associated with said bobbin for gripping thereona loop of thread introduced by said thread guiding means, means forrotating said bobbin to wind thread thereon, a thread severing kniferotatable with said loop taker in a fixed angular position therewithtrailing said loop seizing beak, said thread severing knife traversing apath disposed outwardly adjacent to the periphery of said bobbin, acurved thread positioning arm formed on said bobbin case and extendingoutwardly adjacent to the path of said thread severing knife, cam meansformed on said thread positioning arm from substantially 180 to 270about said loop taker considered from a point opposite said needleaperture and in the direction of rotation of said loop taker forpositioning into the path of said thread severing knife that limb of athread loop extending from said thread gripping means on said bobbin tosaid thread end anchoring means after said limb of thread has been castfrom said loop seizing beak by said take-up mechanism, and a threadaccommodating recess formed in said thread positioning arm between saidbobbin and said needle aperture for positioning out of the path of saidthread severing knife that limb of a thread loop extending from saidthread gripping means on said bobbin to said thread carrying needle.

8. In a lock stitch sewing machine having a rotary loop taker, a threadcarrying bobbin associated with said loop taker and means forreplenishing thread on said bobbin in place in said loop taker includinga bobbin winding member disposed between said loop taker and said bobbinand shiftable into an effective position partially enveloping saidbobbin, means for constraining said bobbin in place in said loop takerand for applying a frictional resistance to turning of said bobbincomprising, an annular bobbin case, means for constraining said bobbincase in place in said loop taker, means for restraining said bobbin casefrom rotation, a thread carrying bobbin formed with a cylindricalflange, an annular seat formed in said bobbin case adapted toaccommodate said bobbin flange, an arm disposed extending radially oversaid bobbin, means pivoting said arm on said bobbin case at one side ofsaid annular seat, complemental bearing means formed directly on saidarm and on said bobbin defining a fixed pivotal axis for turningmovement of said bobbin relatively to said bobbin case, and spring meanscarried by said bobbin case and engaging said pivoted arm for biasingsaid bobbin flange against said annular seat.

References Cited in the file of this patent UNITED STATES PATENTS159,958 ONeil Feb. 16, 1875 388,323 V-annett Aug. 21, 1888 FOREIGNPATENTS 1,224,744 France Feb. 8, 1960

1. IN A LOCK STITCH SEWING MACHINE HAVING A FRAME A THREAD CARRYINGNEEDLE, A LOOP TAKER, A LOOP SEIZING BEAK FORMED ON SAID LOOP TAKERADAPTED TO SEIZE, MANIPULATE AND SHED LOOPS OF NEEDLE THREAD, A THREADCARRYING BOBBIN, MEANS FOR CONSTRAINING SAID BOBBIN IN PLACE IN SAIDLOOP TAKER, AND DRIVE MEANS PERMANENTLY INTERCONNECTING SAID NEEDLE ANDLOOP TAKER FOR INTERRELATED MOTION REQUIRED FOR THE FORMATION OF LOCKSTITCHES, MEANS FOR REPLENISHING THREAD ON SAID BOBBIN IN PLACE IN SAIDLOOP TAKER DURING INTERRELATED MOTION OF SAID NEEDLE AND LOOP TAKER ASREQUIRED FOR THE FORMATION OF LOCK STITCHES COMPRISING, MEANS FORANCHORING A FREE END OF THREAD CARRIED BY SAID NEEDLE RELATIVELY TO SAIDSEWING MACHINE FRAME, THREAD GUIDE MEANS ASSOCIATED WITH SAID LOOP TAKERFOR DIRECTING INTO SAID BOBBIN A LOOP OF SAID ANCHORED NEEDLE THREADSEIZED AND MANIPULATED BY SAID LOOP TAKER LOOP SEIZING BEAK, THREADGRIPPING MEANS ON SAID BOBBIN FOR SECURING THEREON THAT LOOP OF THREADDIRECTED INTO SAID BOBBIN BY SAID THREAD GUIDE MEANS, THREAD SEVERINGMEANS CARRIED FOR MOVEMENT WITH SAID LOOP TAKER IN A PATH EFFECTIVE TOSEVER THAT LIMB OF A LOOP OF NEEDLE THREAD EXTENDING FROM SAID THREADGRIPPING MEANS ON SAID BOBBIN TO SAID THREAD ANCHORING MEANS, AND DRIVEMEANS FOR ROTATING SAID BOBBIN DURING CONTINUED INTERRELATED MOTION OFSAID NEEDLE AND LOOP TAKER AS IS REQUIRED FOR THE FORMATION OF LOCKSTITCHES.